Question

How can I run a select query on a multivalue attribute? Does mysql have a function do select certain data from a multivalue field? Much help is appreciated. Here’s a sample of the problem:

Table

userid      groups
-------------------
  2          2,3,5
  4          1
  9          2,5,10

datatype is char(250) for groups

I want to do a query to select all userids that belong to group 5, in this example it would be userid 2 and 9. So:

userid
------
  2
  9

Any way to go about it with a mysql query? or with php/mysql?

Answer 1

In case the groups datatype is SET

You can use

SELECT * FROM users WHERE FIND_IN_SET('5', groups);

---

UPDATE

In case of char or varchar. You can use this

SELECT * FROM users
WHERE 
     groups LIKE '5,%'
     OR groups LIKE '%,5'
     OR groups LIKE '%,5,%'
     OR groups = '5'